DNA Melting Temperature API
DNA-oligo and PCR-primer maths as an API, computed locally and deterministically. The tm endpoint computes the melting temperature of a primer sequence three ways: the Wallace rule 2·(A+T) + 4·(G+C) for short oligos up to 13 nt, the Marmur–Wallace GC formula 64.9 + 41·(nGC − 16.4)/N for longer ones, and the salt-adjusted 81.5 + 0.41·%GC − 675/N + 16.6·log10[Na+] for a given sodium concentration, and recommends the right method for the length — an eight-base ATGCATGC melts at 24 °C by Wallace, a 20-base 50 %-GC primer at about 51.8 °C by Marmur. The gc-content endpoint reports the GC and AT percentages, the per-base counts and the single-stranded molecular weight. The reverse-complement endpoint returns the complement, the reverse and the reverse complement of a strand. Sequences use A/C/G/T (case-insensitive, whitespace ignored) and [Na+] is in mol/L. Everything is computed locally and deterministically, so it is instant and private. Ideal for molecular-biology, biotech, PCR, primer-design, bioinformatics and lab-automation app developers, oligo and primer calculators, and LIMS software. Estimation formulas for primer design, not a substitute for nearest-neighbour thermodynamics. Pure local computation — no key, no third-party service, instant. Live, nothing stored. 3 endpoints. This is oligo melting temperature; for population-genetics allele frequencies use a genetics API.
api.oanor.com/dnamelt-api